In the provision of wireless communication services within a cellular network, individual geographic areas or “cells” are serviced by one or more base stations. A base station has at least one cellular tower associated therewith, utilizing RF antennas which communicate with a plurality of remote devices, such as cellular phones and paging devices. The tower is then linked with other facilities of the service provider, including a switching office, for handling and processing the wireless communication traffic. The tower might be coupled to the switching office through land lines, or alternatively, the signals might be transmitted or backhauled through microwave backhaul antennas. Another tower might also be involved for delivering the wireless traffic to the switching office or another site. Generally, a tower will have various RF antennas and microwave backhaul antennas associated with each of the different wireless service providers, such as AT&T, Sprint, Verizon, and others having coverage for the area where the tower is located. As may be appreciated, each cellular tower generally accommodates a plurality of RF and/or microwave backhaul antennas.
Traditionally, cellular base stations and towers were owned and operated by the service providers. However, today, such towers are owned by third-party companies who are driven to operate the towers as efficiently and profitably as possible. To that end, and to maximize profits, cellular towers often accommodate multiple service providers desiring coverage in a geographic area. However, there are physical capacity limits for cellular towers which limit the capacity of the towers in handling all of the equipment for all possible service providers. Specifically, a greater number of service providers for a cell or cell sector has translated into additional equipment being loaded onto the tower. However, the physical tower loading must remain within desired parameters for the integrity of the tower.
For example, on a typical cellular tower, multiple providers (Q) each might have sets of 6–9 RF link antennas on a single tower. Such antennas, in addition to their own weight, each require Q×(6–9) cables. In addition to the RF link antennas, there will often be multiple microwave backhaul antennas (P), directed at various orientations around a 360° axis, adding not only additional antenna weight, but also requiring P additional cables or waveguides hanging from the tower. Adding additional service providers and the hardware associated therewith, will therefore, tax the tower to its physical capacity. Furthermore, weight is not the only concern, as the antennas and cables increase wind resistance for towers that must withstand 60 mile/hour winds. Still further, ice on the various antenna hardware and cables will further increase physical strain on a tower. Therefore, the physical capacity of the tower currently limits the ability to serve every interested service provider, and therefore limits the revenue of the tower owners in selling their tower space to service providers.
Simply building more towers is not a desirable solution. In addition to the cost to build and maintain the tower, communities are starting to vigorously protest the location of such towers due to their unsightly addition to the landscape. This is particularly so in densely populated areas where more towers might be needed or coverage is particularly desired by the service provider.
Another revenue limiting issue for tower owners is that there is only one tower top. The most desirable position for a service provider is to be operating from RF link or microwave backhaul antennas positioned at or very close to the top of the tower. The highest amount of revenue, or tower rent fees, for a tower operator is generated by those service providers using equipment at the top of the tower. Those service providers with equipment located below the tower top, understandably, will only pay lesser fees.
Another particular concern for service providers is the shape and direction of their signal beams. Different providers have different demands, thus putting a further burden on tower owners. While tower owners may provide specific beams to a service provider, such an option is often expensive, and will usually require additional equipment on the tower for that specific service provider. Furthermore, offering the service to one tower customer creates a desire by other tower customers, requiring even more equipment and expense to maintain the customers.
Consequently, tower operators have various factors to consider as they sell their tower services to wireless service providers. Traditionally, the tower operators have worked to sell their tower space and to put as much equipment on a tower as they could physically accommodate. The tower owners would like to have every possible service provider on their towers. Of course, every service provider will want the tower top location and will want special considerations, such as specific beam shapes or directions. As such, there exists a tension in the tower market due to limitations in the current technology which limits not only the revenues of the tower owner but also the benefits to be received by a service provider.
Therefore, it is desirable for a tower operator to increase revenues by accommodating every potential service provider customer on the tower.
It is further desirable, both from a revenue standpoint for the tower owner and a performance standpoint for the service provider, to have all service providers located at the tower top.
In addition to accommodating all of the service providers, the tower owner also wants to be able to meet the specific performance criteria of each of their potential service provider customers, including beam considerations, in order to entice them to purchase the services of the tower owner.